Question

why the poles of an electromagnet can be reversed

Answer 1

the poles of an electromagnet can be change by changing the direction of current flowing from it by changing negative and positive terminal

Answer 2

Unlike a permanent magnet, the strength of an electromagnet caneasily be changed by changing the amount of electric current that flows through it. The poles of an electromagnet can even be reversedby reversing the flow of electricity. Anelectromagnet works because an electric current produces a magnetic field.